Resilient foot for instruments and the like



15 A. SCHELGUNOV 2,849,201

RESILIENT FOOT FOR INSTRUMENTS AND THE LIKE Filed Oct. 7, 1953 v INVENTOR I 1 37.17 Alex Schelyunov ATTORNEY tates RESHJENT F061 FUR IPJSTRUMENTg AND THE LIKE Alex Schelgunov, Euclid, Ohio, assignor to Bird Electronic Corporation:

Application October 7, 1953, Serial No. 384,581

12 Claims. ((31. 248-24J This invention relates to resilient mounting devices, particularly those which constitute supporting feet for portable appliances, instruments and containers for various items. The invention is particularly concerned with resilient deformable feet of the type that are received and held in sockets, recesses or openings in the base or pedestal of the article to be supported.

It is well known that small articles such as meters,

instruments and various other devices comprising rigid boxes or containers can be provided with resilient mounts consisting of plugs formed of rubber or the like received in suitable sockets in the base of the device. However, the simple expedient of inserting a rubber plug or cushion in a socket opening through the bottom of the article to be supported has not been entirely satisfactory for a number of reasons. A simple press fit of the rubber plug in the recess does not ordinarily result in a frictional grip sufi'icient to retain the plug during normal usage. Loss of the resilient supporting plugs from small portable.

articles is a not infrequent occurrence. If the recesses and the plugs are so proportioned as to obtain a frictional grip suflicient to retain the plugs in normal usage, it becomes difficult to assemble the plugs in the sockets in original manufacture. Objectionable distortion of and damage to the plugs is increased and where a number of the plugs are used to support an article some may not seat or bottom to the desired predetermined location and the article is unsteady or otherwise improperly supported.

Resilient rubber feet have also been made in the form of molded plugs provided on one end with an enlargement or head which, when received within a suitably shaped socket or recess in the base of the article to be supported, effects a mechanical interlock to hold the plug in place.

One of the problems encountered in such plug type resilient cushions or vibration absorbing feet is in connection with the interlock which must permit the parts to be readily put together in original assembly and which must also retain the parts in assembled relation during the contemplated life of the article being supported. These molded or shaped plugs, while superior to simple friction fit plugs, are difficult to assemble in the mating recesses during original manufacture of the article and are also more expensive to make. Furthermore, by reason of the complemental interfitting relation between the molded plug and the recess therefor, tolerances are critical and a larger number and variety of resilient plugs must be made to provide a line or stock that will satisfy commercial requirements. Additionally, special skill is required in assembly to insure proper interfitting of the molded plugs in theshaped recesses.

The resilient supporting plugs or instrument feet presently available are, or after some use tend to become, loose in the socket so that they are either lost or fail to support the article properly. Plug cushions that maintain adequate interlocking connections with the item supported are complicated in shape, require special assembly procedures and techniques and are costly to manu facture. Since the uses and applications of plug type resilient cushions are legion, it is desirable that a plug be usable with different types and sizes of articles to reduce the inventory a dealer must maintain on hand and the types and sizes a manufacturer must produce.

It is, therefore, the principal object of the present invention to provide a mounting device of the resilient foot type which largely overcomes the above objections and difliculties associated with the earlier resilient foot mounts. In the mounting device of the present invention a complemental relationship exists between the resilient foot of rubber or other suitable deformable material and the rigid base or support member of the article with which the foot is assembled. This relationship, however, is less critical dimensionally than in the case of the complementally shaped plugs and recesses heretofore available by reason of a distention or expansion of the present plug that occurs in assembly.

Another object of the invention is to provide a resilient mount of the insertable plug type which lends itself to rapid and easy assembly in the base or supporting member of the article. More particularly, this aspect of the invention is concerned with the provision of a resilient plug support that can be readily mounted on an inserting tool, in fact can be so proportioned as to retain itself on the stem of a tool, and which can be inserted in the mounting recess by simple axial movement of the stemmed tool, the assembly including means automatically effecting an interlock which holds the resilient plug in place to permit withdrawal of the inserting tool without dislodging the plug.

Another objective is to provide an improved foot or support construction of the character referred to which comprises in combination a rigid member formed with an opening or socket aperture, a hollow mounting member or element that is resilient and deformable and is receivable in the socket, and a distending element or pellet small enough to be received in the socket but large enough to stretch the deformable element when received internally of the deformable element to expand the latter in the establishment of an interlocking connection which holds the elements assembled in the socket aperture or opening of the rigid member.

Another object is to provide a resilient mounting foot assembly which in its broader aspects is embodied in the combination of a deformable tubular member or plug adapted to be inserted into a recess in the base or support member of the article and an expander pellet of relatively hard material which is insertable into the deformable plug. Preferably the expander is inserted by axial movement through the internal chamber of the plug, the expander serving to distend the walls of the plug so as to grip or effect an interlock with the walls of the recess in which the plug is received. In a more refined version the invention contemplates a resilient deformable plug of thimblelike shape providing an internal axial recess closed at one end so that the closed end serves not only to locate the internal expander axially in the plug but also to bear the endwise thrust of an inserting tool used to force the plug into the recess of the supporting member with which it is assembled.

The cushion element is a hollow cup-like or thimble shaped rubber body member formed with an opening preferably at one end, through which the expanding element may be inserted. The article with which the foot or cushion mounting member is to be assembled and which is to be supported by the cushion has a rigid member formed with a suitable aperture or socket into which the cushion mounting member may be inserted for a portion only of its axial length. An element received in the resilient body, preferably by being inserted therein after the body is positioned in the socket aperture,

expands the cushion body into frictional engagement with the walls of the socket. The expansion of the resilient deformable body effects a mechanical interlock of the parts resistant to withdrawal of the deformable body from the socket and the embracing grip of the resilient body on the expander element retains the latter in place.

As a still further refinement and objective of the invention the thimblelike resilient plug mounting member is formed with a circumferential shoulder as by a radial enlargement or flange, preferably adjacent the open end. The engagement of such flange or enlargement with the support member in assembly serves to locate the plug axially in such support member and also to bear the load in compression.

A still further object of the invention is to provide a resilient mount assembly which is simple in design and construction and inexpensive to manufacture in quantity. Other objects and advantages relating to certain novel features of construction and combinations and arrangements of parts are apparent in the following detailed description of a preferred and several alternative embodiments of the invention, this description being made in connection with the accompanying drawings forming a part of the specification.

In the drawings:

Figure 1 is an elevational view, partly in section and with parts broken away, showing the foot or mount structure assembly of the present invention as embodied in the supporting arrangement for a box or container;

Fig. 2 is an expanded view, partly in section and with parts broken away and removed, showing a fragment of the box, the resilient deformable foot and the expander;

Fig. 3 is a fragmentary plan view of the assembly shown in Fig. 1, this view being taken as along the line 33 of Fig. l and enlarged with respect to that figure;

Fig. 4 is a fragmentary view, partly in section and -With parts broken away and removed, showing diagrammatically one method of assembling the resilient mount structure of the present invention by use of a stemmed tool;

Fig. 5 is a fragmentary sectional detail showing another or modified mount structure embodying the principles of the present invention;

Fig. 6 is an elevational detail, partly in section, showing in unstressed condition the resilient foot member of the modification to Fig. 5

Fig. 7 is a fragmentary sectional detail showing a modification of the invention wherein the expander includes a stem and a base which constitutes a support for the article supplemental to that provided by the deformable cushion eiement of the mount structure;

Fig. 8 is an elevational view, partly in section, showing the deformable element of the mount structure of Fig. 7 in its unstressed condition; and

Fig. 9 is a perspective view of the expander used in the modification of Fig. 7.

The resilient mounting device, foot or support construction of the present invention is illustrated in the drawings in combination with an article such as a meter box, indicated generally at A, the resilient feet being assembled with the article for the purpose of supporting the latter as on any suitable surface indicated at 1, which may be a table, bench, counter top or the like. The article A may be any item for which a resilient nonslipping support is desired, the rubber feet of the present invention serving not only to protect the surface 1 and to cushion the article but also to support the article in raised position off the surface in accommodation of surface irregularities. While the supported article is shown as a box of metal or plastic, it is apparent that other articles such as trays, sheets and small machines may be similarly mounted.

Several of the resilient cushions or feet B are assembled with the article A, each of the cushions being interlocked 1' with a rigid support member 2 comprising part of the article A to be supported. Although here shown as the bottom of the instrument box A and integral with the side walls of the box, it is obvious that the rigid support member 2 may comprise a separate plate, stamping or bracket suitably secured or held to the article to be supported. Each of the feet is received through an aperture or opening 3 formed in a portion of the rigid support member or instrument base 2, the latter preferably having an outside substantially flat surface 4. The opening 3 shown is circular in shape for simplicity and economy in manufacture, although square or other noncircular shapes may be employed. The resilient mounting device or foot B is also circular in cross section, with iike advantages, desirably taking the form of an elongated circular sectioned closed end tube.

The resilient feet or support cushions B are formed as by molding of suitable rubber compounds or the like or they may be molded of deformable plastic materials having greater stiffness and less deformability and resiliency than rubber. Rubber is compounded to provide any desired hardness so that the item or article to be supported will not unduly crush or deform the cushion feet in use. The mechanical interlock of the combination of the present invention permits the cushion members to be assembled and retained with greater ease and security than in the case, say, of conventional resilient feet which are formed in molding to provide an interlock with the support member and which do not have the expander C to function in the interlock. In its molded or unstressed shape (Fig. 2) the cushion has an internal cylindrically shaped chamber 6 closed at one end, its entering end, as indicated at 7. At the other or head end the chamber opens at 9 axially through a substantially flat end face 19 of the resilient cushion. The flat end face constitutes a supporting surface which contacts the table or bench surface 1 to support the instrument or other article.

Received within the internal chamber of the cushion B is an expander pellet C which may take the form of a spherically surfaced relatively hard element such as a steel ball. Other types of expanders may, of course, be used, such as those formed of wood, plastic or even rubber of such hardness as will, under normal usage, resist the embracing pressure of the Walls of the cushion B without objectionable deformation and without being expelled from the chamber 6 through the end opening 9.

The resilient cushion member B, while thus being of generally tubular form and preferably of substantially circular cross section, is more precisely defined as being of thimblelike shape, the closed entering end 7 having an external hemispherical surface 11 and an internal hemispherical surface 12 concentric to the external surface ll. The internal cylindrical surface of the chamber 6 is tangent to the closed end hemispherical surface 12 and external cylindrical surface 14 of the cushion is tangent to the external hemispherical surface 11.

As shown in Figs. 2 and 3, the external cylindrical surface lid of the unstressed shank portion of the mounting member is of greater cross sectional area or diameter than the circular opening 3 in the rigid support member 2 so that radial constriction of the mounting or member is required to assemble the cushion member within the opening of the support member. The assembly is effected manually as by placing the hemispherical surface It against the opening 3 in the rigid member and namually turning the cushion member while applying axial pressure thereto. if desired, the elongated stem of a suitable tool 15 (Fig. 4 may be inserted axially into the cylindrical chamber s to engage the closed end 7 of the cushion member and by axial movement serve'to elongate and force the shank portion of the mounting member into the support member opening. By thus applying axial pressure to the inside of the closed end of the mount or member and elongating the shank portion or body of the latter a reduction in section is obtained which reduces the external diameter of the outside surface 14. In this manner a cushion member B having in its .normal molded or unstressed condition an external diameter considerably larger than that of the opening 3 in the support member can be readily inserted into such opening without objectional twisting, marring or scraping of one part against the other.

After the cushion member B has been inserted into the support member recess or opening 3, the cushion member being constricted or circumferentially contracted at its mid section where it is embraced by the support member 2, the expander C is forced into the interior of the chamher in the cushion member through the end opening 9. The expander is moved into the far end of the recess 6 and into engagement with the hemispherical end wall 12. Desirably the stem tool 15 is formed at its end with a spherical recess, or the tool end may be tubular, to receive and locate the expander C on center. Thus the tool may be used to engage and apply force to the expander to move the latter into and along the circular sectioned axial passage 6. The cross sectional areas of the several parts of the resilient foot construction are so proportioned relative to one another that in the passage of the expander C through the opening 3 in the support member 2 there is a radial squeezing or compressing of the walls of the tubular cushion member and an extrusion of the cushion member walls through the support member opening 3.

Upon movement of the expander C axially beyond the opening 3 in the bottom or support member 2 of the article A so as not to be confined by the walls of the opening the tubular walls of the deformable element B are stretched as from the molded or unstressed shape shown in Fig. 2 to the distended shape shown in Fig. 1 in the provision of an interlock which resists withdrawal of the resilient foot from the recess or opening 3. This distention of the resilient element, particularly in the case of the closed end thimblelike form shown, tensions the resilient element to retain the shoulder 16 snugly against the outside fiat surface 4 of the rigid bottom support member 2 of the container or article. The expander C is retained in place, not only by reason of the frictional grip maintained on the expander by the embracing rubber walls of the resilient element B, but also by reason of the mechanical interlock which is obtained by the proportioning of the parts such that, as shown in Fig. 3, the cross section of the internal chamber 6 of the resilient element in the plane of the opening 3 is less than the cross section of the expander C so that withdrawal of the latter through the opening can only be effected by severe distortion of the resilient body of the cushion B.

In assembling the resilient cushion member into the opening in the rigid support member these parts are suitably located in predetermined relative position as by engagement of a shoulder 16 on the cushion member against the flat outside surface 4 of the support member 2 which surrounds the opening 3. The shoulder 16 may preferably comprise the radial face of an annular enlargement or flange 17 formed integrally on the outer end of the cushion member B. In use the weight of the article A may thus normally rest by gravity on the locating shoulder 16 to be transferred through the flange 17 and the body of the cushion member to the supporting surface 1 which is engaged by the fiat circular bottom face 10 on the end of the cushion member.

As an alternative assembly technique the expander C may be inserted axially into the elongated circular sectioned passage 6 of the cushion element and against the end closure wall 12 before the cushion element is placed in the rigid support member. The resulting subassembly is then forced into place through the Opening 3 of the support member 2 as by use of the stemmed tool that is inserted axially into the passage 6 and engages the expander C in the inner end of such passage. Or the ,6 tool 15 may be used to insert the expander into the chamberof the cushion element while the latter is free of the rigid support member and, without removing the tool from the axial passage in the cushion member, the subassembly comprising the cushion member and contained expander is inserted into the recess of the support member. In this procedure the tool 15 serves as a holder for the subassembly which is held on the end of the tool by the frictional grip of the resilient cushion walls on the tool stem.

In the proportioning of the parts to obtain the desired stressed interlock, wherein the body of the cushion member B is distended by the expander and thus maintained under tension, it is not essential that the cross sectional area or diameter of the receiving opening 3 in the support member 2 be less than the diameter or cross sectional area of the outside or cylindrical surface 14 of the cushion member since by making the diameter or cross sectional area of the internal passage 6 less than the diameter or cross sectional area of the expander C the cushion member is distended and interlocked with the support member by the insertion of the expander. Even when, in the preferred arrangement, the cushion body is of larger diameter than the opening or recess in the support member, the expander can be made larger than the chamber in the unstressed cushion body so as to be circumferentially embraced thereby and frictionally held in place though the subassembly be separated from the rigid support member. This latter feature is of obvious advantage, in that the expanders may be inserted into the cushion bodies at the place of manufacture and shipped or otherwise handled until ready for assembly into the instruments or other articles to be supported. A similar captive arrangement is obtained, of course, by molding or otherwise making a portion only of the circular sectioned passage 6 of less diameter than the expander C.

in Figs. 5 and 6 is illusrated a modification wherein the resilient rubber cushion member, here designated by the letter D, is formed as by molding with an annular or circumferentially continuous external groove 20 adjacent the flange shoulder 16.

In its molded or unstressed shape shown in Fig. 6 the cushion D is in general similar to the cushion B described in connection with Figs. 14 modified by the continuous annular groove 20 about its mid section. The installation or assembly of the cushion D in the article F of Fig. 5 is similar to the installation or assembly of the cushion B described above, a stemmed tool similar to the tool 15 being used if desired. The groove 20 receives and effects a mechanical interlock with the rigid support member in which the foot receiving aperture 3 is formed. The aperture 3 in the base or support member of the article may, as in the case of a relatively thin sheet metal article such as illustrated in Figs. 1-4, be of uniform diameter or cross section through the entire thickness of the base. In the case of a cast or molded article having a relatively thick base or support member, such as indicated at 22, Fig. 5, the foot receiving aperture or recess may be counterbored or otherwise formed with an enlarged recess portion 23 which receives a portion of the base flange 17 of the resilient cushion. By such an arrangement the deformable foot or cushion may be substantially wholly recessedwithin the article supported thereby while yet providing a supporting flange 17 of considerable vertical height which is compressed between the support member of the article and the surface on which the deformable cushion rests and is also circumferentially confined by the cylindrical walls of the counterbore. It is apparent, of course, that the cushion B of Figs. 1-4 may likewise be utilized in an assembly having the counterbore recess 23 in a relatively thick base or support member 22.

in the embodiment of Fig. 5 the expander C of Figs. 14 may be employed to effect the distention of the inner closed end of the cushion body D or, if supplemental supporting capacity and a stronger interlock are desired, a

stemmed expander E may be employed. This expander comprises a spherical end 25 and an internal cylindrical stem portion 26 which projects axially through the internal passage or recess 6 of the cushion and terminates short of the open end of such passage. Thus a clearance space 27 is provided between the end of the expander extension 26 and the end face 10 of the resilient cushion such that the weight of the article is carried Wholly by the resilient deformable cushion.

By reason of the location of the expander extension 2a through the recess opening 3, that portion of the annular wall of the deformable cushion that is disposed in the recess is internally supported and dislodgment and withdrawal of the resilient cushion from the support member recess are strongly resisted.

In Figs. 79 is illustrated a still further modified cushion structure embodying an expander G having a spherical head 39, a cylindrical stem 31 and a disclike or button base 32. In this embodiment a resilient cushion H similar in external shape to either the cushion B of Figs. 1-4 or, as shown, to the cushion D of Figs. and 6 having annular groove it about its mid section, is formed with a shallow circular recess coaxial to the internal chamher 6. The recess 35 opens through the flat bottom face 10 of the cushion. The resilient cushion H is inserted through recess opening 3 in the support member 2, as described in connection with Figs. l-4, and the expander G is then inserted manually or otherwise to lock the cushion in place. As shown in Fig. 7, the disc base 32 of the expander is relatively thin and of less extent axially than the recess 35 in the base of the cushion element H in the provision of a clearance space 36 between the expander base and the contact surface 10 on the end of the cushion H.

Under normal loads the weight of the article supported by the resilient foot assembly of Figs. 71O is carried by the resilient face 10 of the cushion H. Under severe or abnormal loads deformation of the base or flange portion 17 of the cushion may permit the base 32 of the expander to contact the support surface, which has the effect of augmenting the load-carrying capacity of the structure.

The present invention thus provides a mounting device comprising a plug type resilient foot or supporting cushion which is simple in design and construction, easily and quickly manufactured at low cost, is made of stand ard readily available materials using conventional machines and processes, and can be quickly and easily assembled as a mount or with the article to be supported thereby. The present resilient foot is adaptable to different types of articles and retains itself securely in position over an extended period of time in a socket or aperture that may vary considerably in size, depth and general shape.

In accordance with the patent statutes the principles of the present invention may be utilized in various ways, numerous modifications and alterations being contemplated, substitution of parts and changes in construe tion being resorted to as desired, it being understood that the embodiments shown in the drawings and described above are given merely for purposes of explanation and illustration without intending to limit the scope of the claims to the specific details disclosed.

What I claim and desire to secure by Letters Patent of the United States is:

l. in combination in an article having a rigid frame member formed with a through opening, a mounting comprising a resilient deformable foot member having an axial recess open through one end and closed at the other end of the foot member, the foot member in its unstressed condition having a shank portion of substantially uniform section symmetric about the axis of the recess and substantially equal in cross sectional area to the cross sectional area of the through opening in the frame member for facile insertion of the foot member shank portion into the frame member opening in assembly, the foot member having an external shoulder defining the outer limit of the shank portion, said shoulder being disposed in a first plane normal to said axis and engaged against one side of the frame member whereby to locate the members axially in assembly, the axial length of the foot member between said first plane and said other end being greater than the axial extent of the through opening from said one to the other side of the frame member so that part of the shank portion of the inserted foot member at said other end of the latter projects from the through opening and beyond a second plane defined by said other side of the frame member, the said axial recess in the foot member extending into and having its closed end within said r netting end part, an expander, said expander being intable axially into the recess through the open end of the latter and into the shank portion and being of greater cross sectional area than that part of the recess extending from the closed end to said first plane whereby insertion of the expander into and along the recess to and locatingly against the closed end of the latter with the foot member inserted in the through opening of the frame member is accompanied by radial compression and axial extrusion of the shank portion of the foot member as the expander travels along that part of the recess located between said one plane and said other plane, the said projecting end part of the inserted foot member being distended by the inserted expander to a cross section greater in area than the cross sectional area of the through opening in the provision of an abutment for engagement with the other side of the frame member obtaining a mechanical interlock strongly resistant to withdrawal of the inserted foot memher from the through opening of the frame member, the deformable material of the shank portion surrounding the recess and located beyond said second plane expanding laterally during passage of the expander therethrough and thereafter contracting to restrict the recess and retain the expander therein, the length of the recess in the shank portion beyond the other side of the frame member being less than the length of the axis of the expander in the direction of insertion into the shank portion to ensure contracting engagement with the trailing end of the expander by the expanded shank portion for holding the expander against said abutment, and the stress in the distended end part of the foot member biasing the shank portion axially in the through opening to retain the shoulder snugly against said one side of the frame member.

2. In combination in an article having a rigid frame member formed with a through opening, a mounting comprising a resilient deformable foot member having an axial recess open through one end and closed at the other end of the foot member, the foot member in its unstressed condition having a shank portion of substantially uniform section symmetric about the axis of the recess and substantially equal in cross sectional area to the cross sectional area of the through opening in the frame member for facile insertion of the foot member shank portion into the frame member opening in assembly, a portion of the foot member at said one end being of greater cross sectional area than the shank portion and constituting a head portion located outside the through aperture of the frame member, the foot member being formed with an external shoulder at the juncture between the shank and head portions, said shoulder being disposed in a first plane normal to said axis and engaged against one side of the frame member whereby to locate the members axially in assembly, the axial length of the foot member between said first plane and said other end being greater than the axial extent of the through opening from said one to the other side of the frame member so that part of the shank portion of the inserted foot member at said other end of the latter projects from the through opening and beyond a second plane defined by said other side of the frame member, the said axial recess in the foot member extending into and having its closed end Within said projecting end part, an expander, said expander being insertable axially into the recess through the open end of the latter and into the shank portion and being of greater cross sectional area than that part of the recess extending from the closed end to said first plane whereby insertion of the expander into and along the recess to and locatingly against the closed end of the latter with the foot member inserted in the through opening of the frame member is accompanied by radial compression and axial extrusion of the shank portion of the foot member as the expander travels along that part of the recess located between said one plane and said other plane, the said projecting end part of the inserted foot member being distended by the inserted exstrongly resistant to withdrawal of the inserted foot member from the through opening of the frame member, the deformable material of the shank portion surrounding the recess and located beyond said second plane expanding laterally during passage of the expander therethrough and thereafter contracting to restrict the recess and retain the expander therein, the length of the recess in the shank portion beyond the other side of the frame member being less than the length of the axis of the expander in the direction of insertion into the shank portion to ensure contracting engagement with the trailing end of the expander by the expanded shank portion for holding the expander against said abutment, and the stress in the distended end part of the foot member biasing the shank portion axially in the through opening to retain the shoulder snugly against said one side of the frame member.

3. In combination in an article having a rigid frame member formed with a through opening, a mounting comprising a resilient deformable foot member of circular section having an axial recess open through one end and closed at the other end of the foot member, the foot member in its unstressed condition having a cylindrical shankportion symmetric about the axis of the recess and substantially equal in cross sectional area to the cross sectional area of the through opening in the frame member for facile insertion of the foot member shank portion into the frame member opening in assembly, the foot member having an external circumferentially extending radial shoulder defining the outer limit of the shank portion, said shoulder being disposed in a first plane normal to said axis and engaged against one side of the frame member whereby to locate the members axially in assembly, the axial length of the foot member between said first plane and said other end being greater than the axial extent of the through opening from said one to the other side of the frame member so that part of the shank portion of the inserted foot member at said other end of the latter projects from the through opening and beyond a second plane defined by said other side of the frame member, the said axial recess in the foot member extending into and having its closed end within said projecting end part, a spherical expander, said expander being insertable axially into the recess through the open end of the latter and into the shank portion and being of greater cross sectional area than that part of the recess extending from the closed end to said first plane Whereby insertion of the expander into and along the recess to and locatingly against the closed end of the latter with the foot member inserted in the through opening of the frame member is accompanied by radial compression and axial extrustion of the shank portion of the foot member as the expander travels along that part of the recess located between said one plane and said other plane, and whereby the said projecting end part of the inserted foot member shank portion is distended to an increased diameter providing an abutment for engagement with the other side of the frame member obtaining a mechanical interlock strongly resistant to withdrawal of the inserted foot member, the deformable material of the shank portion surrounding the recess and located beyond said second plane expanding laterally during passage of the expander therethrough and thereafter contracting to restrict the recess and retain the expander therein, and the length of the recess in the shank portion beyond the other side of the frame member being less than the length of the axis of the expander in the direction of insertion into the shank portion to ensure contracting engagement with the trailing end of the expander by the expanded shank portion for holding the expander against said abutment.

4. In combination in an article having a rigid frame member formed with a through opening, a mounting comprising a resilient deformable foot member of circular section having an axial recess open through one end and closed at the other end of the foot member, the foot member in its unstressed condition having a cylindrical shank portion symmetric about the axis of the recess and substantially equal in cross sectional area to the cross sectional area of the through opening in the frame member for facile insertion'of the foot member shank portion into the frame member opening in assembly, the foot member having at said one end a cylindrical head portion of greater diameter than the shank portion, the foot member being formed with an external circumferentially extending radial shoulder at the juncture between the shank and the head portions, said radial shoulder being disposed in a first plane normal to said axis and engaged against one side of the frame member whereby to locate the members axially in assembly, the axial length of the foot member between said first plane and said other end being greater than the axial extent of the through opening from said one to the other side of the frame member so that part of the shank portion of the inserted foot member at said other end of the latter projects from the through opening and beyond a second plane defined by said other side of the frame member, the said axial recess in the foot member extending into and having its closed end within said projecting end part, an expander, said expander being insertable axially into the recess through the open end of the latter and into the shank portion and being of greater cross sectional area than that part of the recess extendingfrom the closed end to said first plane whereby insertion of the expander into and along the recess to and locatingly against the closed end ofthe latter with the foot member inserted in the through opening of the frame member is accompanied by radial compression and axial extrusion of the shank portion of the foot member as the expander travels along that part of the recess located between said one plane and said other plane, and whereby the said projecting end part of the inserted foot member shank portion is distended to an increased diameter providing an abutment for engagement with the other side of the frame member obtaining a mechanical interlock strongly resistant to withdrawal of the inserted foot member, the deformable material of the shank portion surrounding the recess and located beyond said second plane expanding laterally durmg passage of the expander therethrough and thereafter contracting to restrict the recess and retain the expander therein, and the length of the recess in the shank portion beyond the other side of the frame member being less than the length of the axis of the expander in the direction of insertion into the shank portion to ensure contracting engagement with the trailing end of the expander by the expanded shank portion for holding the expander against said abutment.

5. In combination in an article having a rigid frame member formed with a through opening, a mounting comprising a resilient deformable foot member of circul l lar section having an axial recess open through one end and closed at the other end of the foot member, the foot member in its unstressed condition having a cylindrical shank portion symmetric about the axis of the recess and substantially equal in cross sectional area to the cross sectional area of the through opening in the frame member for facile insertion of the foot member shank portion into the frame member opening in assembly, the foot member having an external circumferentially extending radial shoulder defining the outer limit of the shank portion, said shoulder being disposed in a first plane normal to said axis and engaged against one side of the frame member whereby to locate the members axially in assembly, said other end of the foot member being substantially hemispherical in external shape and having a radius of curvature approximately equal to that of cylindrical body portion, the axial length of the foot member between said first plane and said other end being greater than the axial extent of the through opening from said one to the other side of the frame member so that part of said shank portion including said hemispherical end of the inserted foot member projects from the through opening and beyond a second plane defined by said other side of the frame member, the said axial recess in the foot member extending into and having its closed end within said hemispherical end of the foot member, an expander, said expander being insertable axially into the recess through the open end of the latter and into the shank portion and being of greater cross sectional area than that part of the recess extending from the closed end to said first plane whereby insertion of the expander into and along the recess to and locatingly against the closed end of the latter with the foot member inserted in the through opening of the frame member is accompanied by radial compression and axial extrusion of the shank portion of the foot member as the expander travels along that part of the recess located between said one plane and said other plane, the said projecting end part of the inserted foot member being distended by the inserted expander to a cross section greater in area than the cross sectional area of the through opening in the provision of an abutment for engagement with the other side of the frame member obtaining a mechanical interlock strongly resistant to withdrawal of the inserted foot member from the through opening of the frame member, the deformable material of the shank portion surrounding the recess and located beyond said second plane expanding laterally during passage of the expander therethrough and thereafter contracting to restrict the recess and retain the expander therein, and the length of the recess in the shank portion beyond the other side of the frame member being less than the length of the axis of the expander in the direction of insertion into the shank portion to ensure contracting engagement with the trailing end of the expander by the expanded shank portion for holding the expander against said abutment.

6. A two-piece blind fastener device of the type described adapted to be applied from the exposed surface to the blind surface of an apertured workpiece, and comprising a deformable elastic shank portion for insertion through the workpiece and an enlarged integral head portion for overlying the exposed surface of the workpiece, a passageway extendin axially through said head portion and into said shank portion, a rigid pellet having a cross section transversely of the passageway similar to, but greater than the said passageway in said shank portion, said pellet being insertable through the passageway in said head portion and into the shank portion thereby deforming said shank portion laterally to provide an abutment for engagement with the blind surface of the workpiece, the deformable material surrounding said passageway in the shank portion and within said aperture expanding laterally during passage of the pellet therethrough and thereafter contracting to restrict the passageway and retain the pellet therein, the length of said passageway in the shank portion beyond the blind surface of the workpiece being less than the length of the axis of the pellet in the direction of insertion into the shank portion to ensure contracting engagement with the trailing end of the pellet by the expanded shank portion for holding the pellet against said abutment, and abutment means at the entering end of the shank portion preventing passage of the pellet therethrough.

7. A two-piece blind fastener as claimed in claim 6, wherein the pellet is a substantially ball-like spherical element.

8. A two-piece blind fastener as claimed in claim 6., wherein the juncture between the passageway in the head rtion and the passageway in the shank portion comg 1 a throat which is expanded during insertion of the pellet into the passageway in the shank portion.

9. A two-piece blind mounting of the type describel adapted to be applied from the exposed surface to the alin surface of an apertured workpiece and comprising a deformable elastic member having a shank portion formed with an entering end for insertion through the workpiece and an enlarged integral head portion for overlying the exposed surface of the workpiece, said member being formed with a recess extending axially throughsaid head portion and into said shank portion, an expander pellet having a cross section transversely of the passageway greater than the said passageway said shank por' tion, said pellet being inserted through the passageway in said head portion and into the shank portion thereby deforming said shank portion laterally to provide an abutment for engagement with the blind surface of the workpiece, the deformable material surrounding said pasgeway in the shank portion and within said aperture ding laterally during passage of the pellet lherethrougu and thereafter contracting to restrict the passageway and retain the pellet therein, the length of said passageway in the shant portion beyond the blind surface of the wo'kpieco beii less than the length of the axis of the pellet in the direction of insertion into the shank portion to ensure contracting engagement with the trailing end of the pellet by the expanded shank portion for holding the pellet against said abutment, and abutment means at the entering end of the shank portion preventing assage the pellet therethrough.

10. A two-piece blind mounting of the t pe described adapted to be applied from the exposed surface to the blind surface of an apertured workpiece and comprising a deformable elastic member having a shank portion formed with an entering end for insertion through the workpiece and an integral head portion formed with external radial shoulder means spaced axially from the entering end for en aging the exposed surface of the workpiece to locate the member axially in the aperture of the latter, said member being formed with a recess extending axially through said head portion and into said shank portion, an expander pellet having a cross section transversely of the passageway greater than the s 1.. passageway in said shank portion, said pellet being inertable through the passageway in said head portion into the shank portion thereby deforming said shank portion laterally to provide an abutment for engagement with the blind surface of the workpiece, the deformable material surrounding said passageway in the shank portion and within said aperture expanding laterally durihg pas sage of the pellet therethrough and thereafter contracti to restrict the pasageway and retain the pellet therein, the length of said passageway in the shank portion beyond the blind surface of the workpiece being less than the length of the axis of the pellet in the direction of insertion into the shank portion to ensure contracting engagement with the trailing end of the pellet by the expanded shank portion for holding the pellet against said abutment, and abutment means at the entering end of the shank portion preventing passage of the pellet therethrough.

13 11. A two-piece blind mounting as claimed in claim 10 wherein the head portion has a substantially flat end face normal to the axis of the passageway and such end face is formed with a recess continuous with and of larger cross sectional area than the portion of the passageway extending through the shank portion of the member.

12. A two-piece blind mounting of the type described adapted to be applied from the exposed surface to the after contracting to restrict the passageway and retain the pellet therein, the length of said passageway in the shank blind surface of an apertured workpiece and comprising a deformable elastic member having a shank portion formed with an entering end for insertion through the workpiece and an enlarged integral head portion for overlying the exposed surface of the workpiece, said member being of circular section throughout its length and having a recess extending axially through said head portion and into said shank portion, an expander pellet having a cross section transversely of the passageway greater than the said passageway in said shank portion, said pellet being insertable through the passageway in said head portion and into the shank portion thereby deforming said shank portion laterally to provide an abutment for engagement with the blind surface of the workpiece, the deformable material surrounding said passageway in the shank portion and within said aperture expanding lateral- 1y during passage of the pellet therethrough and thereportion beyond the blind surface of the workpiece being less than the length of the axis of the pellet in the direction of the insertion into the shank portion to ensure contracting engagement with the trailing end of the pellet by the expanded shank portion for holding the pellet against said abutment, and abutment means at the enteringend of the shank portion preventing passage of the pellet therethrough.

References Cited in the file of this patent UNITED STATES PATENTS 608,178 Cock Aug. 2, 1898 843,763 McLauglin Feb. 12, 1907 1,124,828 Woodward Jan. 12, 1915 2,344,717 Mills et al Mar. 21, 1944 2,367,883 Miller Jan. 23, 1945 2,398,532 Keehn Apr. 16, 1946 2,453,991 Kaernmerling Nov. 16, 1948 FOREIGN PATENTS- 625,223 Great Britain June 23, 1949 467,665 Italy Dec. 14, 1951 

